<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>! 操作符</title>
    <style>
        seciton {
            padding: 10px;
        }
    </style>
</head>
<body>
    <h1>! 操作符示例</h1>
    <section>
        <ul>
            <li>!1</li>
            <li>!!1</li>
            <li>!true</li>
            <li>!!true</li>
            <li>!!'true'</li>
            <li>!![]</li>
            <li>!!{}</li>
        </ul>
    </section>
</body>
</html>